This invention relates to a process and device for detecting the presence of insects or insect larvae in a solid substrate, e.g. wood, by observing their specific behavior (behavioral pattern).
Insects and insect larvae living in wood cause, in some cases, considerable damage to timber and artificial objects. The early detection of noxious organisms in wood is rendered difficult by the lack of effective tests operating free from interference, as is the establishment of the effectiveness of treatment measures. The standard specifications, which are associated with long exposure times of the test organisms, for the determination of the effectiveness of wood protection agents, serve, as a rule, also as a--time --intensive--basis for the testing of new active substances in the foreground of production. In this case, too, there is a lack of test processes with which changes in the behavior of test organisms can be detected rapidly and reliably.
In industrial practice, a determination of the behavior of insects (insect larvae) living in wood is
5 undertaken in accordance with the standards, DIN EN 20, DIN EN 21, DIN EN 22 and DIN EN 47. In this case, the number of surviving test organisms is employed to draw conclusions concerning changes in behavior; furthermore, these standards permit observations using X-ray systems. In basic biological research, since the invention of the carbon microphone, repeated use has been made of devices which make audible, or record in a nonspecific manner, the noises generated by insects (insect larvae) living in wood. Note A. E. EMMERSON and R. C. SIMPSON 1929 in Science, 1929, Vol. 69, pages 648-649.
The above indicated DIN processes for the determination of changes in behavior of insects or insect larvae living in wood require, in some cases, very long exposure times of the test organisms (between 6 and 52 weeks, depending upon the type of organism) and, in such a case, do not permit any guaranteed statements concerning the temporal progression of changes in behavior. An unambiguous determination of the current behavior of the test organisms is (without suspending the test), therefore, impossible.
The processes employed in basic biological research for a specific set of problems record noises and vibrations in an entirely non-specific manner. In the case of the construction of the test arrangement in low-noise and low-vibration chambers, it is possible to detect in a controlled manner the noises and vibrations generated by insects (insect larvae) living in the wood.